I have not been, but, Germain's is reputed to be the best or one of the best on Oahu if one can believe prior postings here and elsewhere. You often see this one recommended by folks who live in Honolulu and take their visitors there.
Normally if you go through an agency they will have transportation arranged for you, unless you are renting a vehicle. The luau starts I think around 2 or 3. And of course traffic is always really bad in honolulu it took us 40 minutes to get there and the hotel we were in was about 10-15 minutes from the pier. Traffic isn't as bad on the way back.